Practical MIG Welding: Cooling
Watch This Course
$199 USD
-OR-
Or
8 easy payments of only $24.88 USD
Instant access. Easy checkout. No fees.
Cooling
01.39
| 00:00 | With the weld complete we can now flip up our mask and take a look at the weld area for any signs of issues that may need addressing. |
| 00:06 | The most common problem that we're going to find will be inclusions in the weld from either dirty materials or a lack of shielding gas. |
| 00:13 | This will present itself as discolouration or porosity which is seen in the weld as little air holes. |
| 00:18 | They can be difficult to remove and often need grinding out and rewelding. |
| 00:23 | Welding directly over these may make the situation worse so it is best to grind it back and reweld the affected area. |
| 00:29 | Brown discolouration on steel or blackening on aluminium happens from a lack of shielding gas or contaminants coming out of the material we're welding. |
| 00:37 | This can be a common issue in aluminium repairs because some aluminium is porous and can be impregnated with oils over time. |
| 00:45 | With our weld completed, there's one final step we can take to ensure the strength of the part is retained. |
| 00:51 | When our metal cools, it slightly contracts and moves and if this happens at a rapid rate, we might run into problems with the part pulling or warping out of shape. |
| 00:59 | Some welders get impatient and like to rapid cool their part by quenching it in water and we cannot recommend this technique as the rapid heat loss will affect the molecular structure of the steel, causing strength and integrity issues. |
| 01:11 | To maintain the structure of all metals, it's recommended that the workpiece is left to air cool on the bench. |
| 01:17 | And if you work in a communal environment, remember to put a sign labelled hot next to the material to let others know. |
| 01:23 | Remember, practice makes perfect, be confident and if you always make sure that your materials are clean, the contact tip and nozzle is in good condition and your settings are all right, you'll be well on your way to achieving the perfect weld. |
